/* 
 * Copyright (c) 2004-2005 Massachusetts Institute of Technology. This code was
 * developed as part of the Haystack (http://haystack.lcs.mit.edu/) research 
 * project at MIT. Permission is hereby granted, free of charge, to any person
 * obtaining a copy of this software and associated documentation files (the 
 * "Software"), to deal in the Software without restriction, including without 
 * limitation the rights to use, copy, modify, merge, publish, distribute, 
 * sublicense, and/or sell copies of the Software, and to permit persons to whom
 * the Software is furnished to do so, subject to the following conditions: 
 * 
 * The above copyright notice and this permission notice shall be included in 
 * all copies or substantial portions of the Software. 
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER  
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE. 
 */

/*
 * Created on Jul 26, 2005
 */
package edu.mit.csail.relo.parts;

import org.eclipse.gef.EditPart;
import org.eclipse.gef.commands.Command;
import org.eclipse.gef.editpolicies.GraphicalNodeEditPolicy;
import org.eclipse.gef.requests.CreateConnectionRequest;
import org.eclipse.gef.requests.ReconnectRequest;

import edu.mit.csail.relo.modelBridge.ArtifactRel;
import edu.mit.csail.relo.modelBridge.DerivedArtifact;
import edu.mit.csail.relo.modelBridge.NamedRel;

/**
 * EditPolicy for Creating/Reconnecting ArtifactRel. Also makes sure that
 * source&targets are not DerivedArtifact's and that Reconnection only happens
 * for AnnotatedRel's
 * 
 * @author vineet
 */
public class ArtifactRelModificationEditPolicy extends GraphicalNodeEditPolicy {

    protected boolean validConnectionPoint(EditPart ep) {
        return (ep instanceof ArtifactEditPart);
    }

    protected ArtifactEditPart getNonDerivedParent(EditPart ep) {
        while (ep!=null && ep.getModel() instanceof DerivedArtifact) {
            ep = ep.getParent();
        }
        return (ArtifactEditPart) ep;
    }

    protected boolean validReConnectionLink(Object rel) {
        return (rel instanceof NamedRel);
    }

    @Override
    protected Command getConnectionCreateCommand(CreateConnectionRequest request) {
        Object link = request.getNewObject();
        if (link instanceof ArtifactRel && validConnectionPoint(getHost())) {
            Command cmd = new ArtifactRelCreationCommand((ArtifactRel) link, getNonDerivedParent(getHost()));
            request.setStartCommand(cmd);
            return cmd;
        } else
            return null;
    }
    
    @Override
    protected Command getConnectionCompleteCommand(CreateConnectionRequest request) {
        ArtifactRelCreationCommand cmd = (ArtifactRelCreationCommand)request.getStartCommand();
        if (validConnectionPoint(getHost())) {
            cmd.setTarget( getNonDerivedParent(getHost()) );
            return cmd;
        } else
            return null;
    }

    @Override
    protected Command getReconnectSourceCommand(ReconnectRequest request) {
        if (validReConnectionLink(request.getConnectionEditPart().getModel())
                && validConnectionPoint(request.getTarget())) {
            
            ArtifactRelReConnectionCommand aRRCCmd = 
                new ArtifactRelReConnectionCommand((ArtifactRelEditPart) request.getConnectionEditPart());
            
            aRRCCmd.setNewConnectionPoints(
                    getNonDerivedParent(request.getTarget()),
                    (ArtifactEditPart) request.getConnectionEditPart().getTarget()
                    );
            
            return aRRCCmd;
        } else
            return null;
    }

    @Override
    protected Command getReconnectTargetCommand(ReconnectRequest request) {
        if (validReConnectionLink(request.getConnectionEditPart().getModel())
                && validConnectionPoint(request.getTarget())) {
            
            ArtifactRelReConnectionCommand aRRCCmd = 
                new ArtifactRelReConnectionCommand((ArtifactRelEditPart) request.getConnectionEditPart());

            aRRCCmd.setNewConnectionPoints(
                    (ArtifactEditPart) request.getConnectionEditPart().getSource(),
                    getNonDerivedParent(request.getTarget())
                    );

            return aRRCCmd;
        } else
            return null;
    }
}